Explaining the Brain to Lyra Belaqua
by Rjalker
Summary: I turned in a fanfic for a homework assignment. I got a 100%. Completely spoiler free and surprisingly educational.


Lyra was bored.

Her teacher for the day—a scholar, or _smart person_—was standing at the front of the room that was used for her lessons, his mouth moving and sounds coming out, but none that she could understand.

Perched on her shoulder in the form of a small, ice-colored dragon, Pan turned to whisper in her ear, "Did he just say _Medusa_?"

Sir Ponytail, as she enjoyed calling her teacher in her head, didn't notice that Pan had said anything, but the sparrowhawk on the perch next to him certainly had.

She lifted one wing, causing Lyra's teacher to stop talking, and swooped over to land on her desk.

"That's _medulla_." She corrected, "Not Medusa."

Pan, unused to being noticed, turned into a mouse and hid behind Lyra's hair. "Oh." He said quietly.

The small hawk nodded, then looked up at Lyra. "You don't know what that means, do you?"

As embarrassed as her daemon—which is said the same way as _demon_, though it doesn't mean the same thing—Lyra shook her head silently.

Sir Ponytail sighed, and Lyra could have sworn the sparrowhawk rolled her eyes.

"Terallyn," Sir Ponytail said, waving his hand, "Perhaps _you_ will have better luck teaching young miss Belacqua here than I have." He sat down at the desk that was pushed against one of the walls for his use.

The sparrowhawk—Terallyn—flew back to her original perch, and cleared her throat. "Pantalaimon," She said sternly, addressing Pan by his full name, "I expect you to be paying attention as well. Sit on the desk, please, where I can see you."

Surprised—because most of their other teachers didn't seem to notice if they were paying attention or not—Pan turned into a small spotted owl, and perched on the edge of the desk.

"Thank you." The sparrowhawk said. "Now, first off, we will start again with the _medulla_. Can either of you tell me what it does?"

Pan turned his head around all the way to look at Lyra, but she was just as confused as he was. They didn't even know what part of the body they were supposed to be talking about.

"Um, no, ma'am." Lyra said, deciding that it would probably be best not to lie in this situation.

"Alright," Terallyn said, shifting her wings, "Lyra, I want you to lift your hand to your neck, and feel your heartbeat." She waited until Lyra had done so before instructing, "Good. Now, try to control how fast your heart beats. Pan, you do the same."

Lyra frowned. "But that's impossible," She said, "You can't control your heart. It just goes…by itself."

Pan nodded his agreement.

Terallyn bowed her head, "Exactly!" She said, "The medulla is the part of the brain that controls the things that we can't. It's what makes our heart beat, and lets us breathe without even thinking about it. Without the medulla, we would never be able to sleep, because we would have to focus on breathing all the time."

Pan suddenly perked up, and shifted into a goldfinch to hop up and down on the desk, "Oh!" He cried, "So that's what gets messed up when a ghost eats you?"

Terallyn frowned. "What do you mean?"

It was Lyra who answered this time, "There's ghosts, see, up in the north. They fly on the wind, and when they catch you, they steal your breath away, so that your daemon has to keep your heart beating so that you don't die."

Sir Ponytail cleared his throat, "Yes, I believe you would be correct. If, of course, such creatures existed."

"Next up," Terallyn said, before the conversation could get off track, "Is the thalamus. The thalamus is the part of your brain that tells the rest of your body what you can see, hear and feel. The parietal lobe helps as well." She brushed one of Pan's wings with her own to demonstrate. "The thalamus is also what tells you when it's time to go to sleep, and when it's time to wake up. Does that make sense?"

"The medulla makes your heart beat, and the thalamus tells you what's around you." Lyra and Pan repeated back.

"There is also the _hypo_thalamus, which deals with instinctive drives, like hunger and thirst, and, not to confuse the two, there is the hippocampus, which turns our short-term—meaning, memories that were recently formed—into long-term memories. The hippocampus is the reason you are able to remember things from a long time ago. The temporal lobes, which are right above your ears, also help with this, along with sounds."

Once again, the two nodded in understanding. Terallyn smiled proudly to herself as she flew the short distance back to her perch at the front of the room. This was probably the longest any scholar had held Lyra Belacqua's attention.

"Are there other things that help you see and hear?" Pantalaimon asked, tilting his head to the side, "If you hit your head, would you go blind if the thalamus was hurt?"

Behind the desk, Sir Ponytail (whose real name was Sir Parrendale) nodded, his hands folded in front of him, "Yes, Pantalaimon, there are other parts of the brain that help you see. The occipital lobe plays a major part in processing information that your eyes gather."

"If you hit your head hard enough," Terallyn added, "It's possible that you could go blind. Why do you ask?"

Lyra remembered the time she'd fallen off the roof (it had just rained, so it wasn't _her_ fault) and had to have Pan guide her around for the next two days because her vision was blurry. (Not to mention her head hurt.) "No reason." She said simply, and then, to distract them from the topic, suddenly blurted, "Are brains made out of worms?"

Terallyn seemed taken aback, and glanced at Sir Parrendale (Lyra liked them enough now to call him by his real name) in confusion. Pan tilted his head to the side, and transformed back into the spotted owl he'd been before. "All the drawings of brains in our book look like they're covered in worms." He clarified.

Terallyn shook her head slightly, "Those aren't worms, though they do look like them, don't they?" She laughed, "No, those are called _convolutions_. They're folds in the brain."

Lyra nodded, glad her teacher hadn't looked too closely at her earlier question. A lot of the scholars knew she and Roger climbed on the roofs, (because they couldn't resist throwing things at them whenever they saw an unsuspecting pair beneath them) but that didn't mean she was allowed to. If anyone told the Master that she'd fallen and gotten hurt, they would probably lock all the windows she used to get up there.

Sir Parrendale stood, and moved back to the front of the room, apparently deciding that Lyra and Pantalaimon were paying enough attention for _him_ to try teaching them again. He lifted one hand to point at his forehead, "The frontal lobe," He said, "Is what lets us speak, imagine, and plan for the future. It also helps us tell the difference between right and wrong."

Pan turned his head around to blink narrowed black eyes at Lyra meaningfully. He was always trying to stop her when she got her crazy ideas in her head—like sneaking down to the catacombs and stealing coins from the skulls of scholars who were buried there, which they'd paid for when the ghost of a man whose daemon coin they'd moved scared them almost to death—and she stuck her tongue out at him in return.

Sir Parrendale cleared his throat to regain their attention, and, after they were watching again, moved his hand from his forehead to the left side of his head. "This," He said, "Is called the left hemisphere. It is the part of your brain that deals with language, logic, and numbers. The right side—" he moved his hand to the other side of his head, "The right hemisphere, deals with creativity, depth perception—which tells you how far away things are when you look at them—and the ability to recognize faces."

Lyra lifted one hand to tap against the right side of her head. "So if I hurt this side of my brain, I wouldn't be able to recognize people?"

Terallyn nodded.

Pan snickered, "Then you'd actually have to listen to me," He said, turning into an ermine to grin at her, "Since you'd have to use the other side of your brain."

Lyra stuck her tongue out again.

Terallyn lifted her wings to get their attention before they could get completely off topic. There was only one part of the brain left for them to learn for that day, and she didn't want to lose them right when the lesson was about to end. "Pantalaimon, Lyra, back to the topic, please." She said, her voice just stern enough that they listened.

Both turned back to face her and Sir Parrendale with sheepish smiles. "Sorry." Pan said, lowering his head slightly.

"That's quite alright." Sir Parrendale said, smiling, "There's just one last thing before we'll let you go for the day."

Both students sat up straight immediately.

"The corpus callosum," Terallyn said, hopping down from her perch onto the desk again, "Is what connects the right side of your brain to the left, and lets you do multiple things at once."

Again, both nodded in understanding, obviously eager to leave. Lyra started to stand, thinking that the lesson was over, but Sir Parrendale raised one hand to stop her. "Just one moment, please, Lyra." He moved back over to the desk and pulled a piece of paper out of a drawer. He handed it to her. "This is a list of the parts of the brain that we discussed today, what they do," He said, pointing out the drawing of a head with arrows leading away from it, "And where they are located. Promise me you'll study it?"

He stuck one hand out for her to shake.

Lyra hesitated only a moment before taking his hand and shaking it. "Alright, I will." She said, then, "Can we go now?"

Sir Parrendale sighed heavily, buy Lyra could tell he was joking. "Yes, yes," He said, "You may go."

Without another word, Lyra and Pantalaimon—who was in the form of a hawk so that he could fly after her—raced excitedly out of the room, leaving their teachers to tidy up the room.

Later that day, Lyra and Pantalaimon could be found surrounded by a crowd of servant children and their daemons as they hid in the bushes outside the collage's courtyard, telling them horror stories of kids whose chests had been opened up by ghosts, and their daemons, who had to keep their lungs and heart going so they didn't die, because the ghost had broken something in their head, and they couldn't do it themselves.


End file.
